WO2023216418A1

WO2023216418A1 - Bow-and-arrow system for shooting simulation, and simulation method for arrow shooting

Info

Publication number: WO2023216418A1
Application number: PCT/CN2022/107389
Authority: WO
Inventors: 曾胜财
Original assignee: 厦门青凤鸾智能科技有限公司
Priority date: 2022-05-12
Filing date: 2022-07-22
Publication date: 2023-11-16
Also published as: CN115265270A; CN115265270B

Abstract

A bow-and-arrow system for shooting simulation, and a simulation method for arrow shooting. The bow-and-arrow system comprises a bow-and-arrow apparatus and a simulation apparatus (90). The bow-and-arrow apparatus is provided with a bow grip (10), a bowstring (20), an arrow shaft (30) and a cylinder body (40), wherein the arrow shaft (30) slidably passes through the cylinder body (40), and the tail end of the arrow shaft (30) is provided with a through hole (32) for the bowstring (20) to pass through; and the arrow shaft (30) is provided with several sensing grooves (31). The bow-and-arrow apparatus further comprises a speed measurement sensor (50), a sighting sensor (60), a main control module (70) and a data transmission apparatus (80), wherein the speed measurement sensor (50) detects information of the sensing grooves (31) in the arrow shaft (30); the sighting sensor (60) detects sensing data of the arrow shaft (30) in real time; and the main control module (70) respectively performs calculation according to the information of the sensing grooves (31) and the sensing data, so as to obtain the speed of the arrow shaft (30) when leaving the bowstring (20) and Euler angle data when the arrow shaft (30) leaves the string, and sends said speed and the Euler angle data to the simulation apparatus (90). The simulation apparatus (90) obtains an elevation angle of the arrow shaft (30) according to the Euler angle data, corrects the elevation angle according to said speed and a set range, then simulates the flight trajectory of the arrow shaft (30) according to said speed and the corrected elevation angle, and determines a hit position on a target.

Description

A bow and arrow shooting simulation system and a bow and arrow shooting simulation method

Technical field

The present invention relates to the field of shooting simulation, and in particular, to a bow and arrow system for simulating shooting and a simulation method for bow and arrow shooting.

Background technique

Currently, the archery experience on the market requires specific venues and equipment to experience the fun of archery training, which brings some inconvenience to people. In order to allow people to have archery entertainment and training on different occasions, a new method has emerged. A kind of bow and arrow product that simulates shooting, which usually includes a bow and arrow device and a simulation device. By collecting relevant parameters of the bow and arrow device, the simulation device simulates the flight trajectory of the arrow shaft and simulates the target effect, so that users can enjoy an experience close to real archery. without being restricted by occasion.

At present, simulated shooting usually uses coarse-grained virtual simulation, and only performs rough empirical conversions based on the tension or pressure of the bow and arrow. The principle is similar to the ancient soldiers who can shoot as far as the number of stones of the bow and arrow. Using this method is very inaccurate. It does not consider the quality of the arrow, the actual flight speed of the arrow, and the flight angle. It lacks authenticity and the effect of virtual simulation is not very good. Although some use multi-point sampling, and even measure the force value and convert it into acceleration, the sampling frequency is not high enough to accurately calculate the accurate data of acceleration, and in the calculation of converting acceleration into speed, due to insufficient sampling, The distortion of data is very serious, resulting in unreality of virtual reality and poor user experience.

Acceleration sensors are also used to test the acceleration of arrows and then calculate the speed of the arrow. This solution requires increasing the acceleration sampling frequency in order to restore the speed of the arrow as much as possible. After the acceleration per unit time is obtained, the integral accumulation algorithm can be used to finally obtain the speed value of the arrow. That is, the sampling frequency requirement is high and the calculation method is complicated; due to the performance limitations of the acceleration sensor, accurate data cannot be measured and will reach its Data cap for testing.

technical problem

In terms of obtaining the angle of the arrow, there are six-axis sensors or nine-axis sensors, which basically only use the sensor's three-axis accelerometer (measuring acceleration at the same time) and angular velocity sensor (ie: gyroscope) to measure the angle. The focus is on acceleration and angular velocity; and because the sensor is not placed on the arrow or bowstring, the real acceleration is not measured. Some real bows and arrows even have a longer range (the elasticity of the bowstring is relatively large), resulting in the acceleration sensor measurement Failure (basic measurement range exceeded). Furthermore, since the scene used is usually a flat game (X-Y axis), it basically only uses the gyroscope to measure the angular velocity (Y-axis declination), without considering the elevation angle (spatial position) of the magnetic induction sensor (ie: electronic compass) based on the Z-axis. ), causing distortion in the simulation. Traditional angle positioning requires the use of aurora gyroscopes or optical base stations or multi-pupil cameras to ensure that the angle is corrected during long-term use. The usage scenarios are limited and require equipment and networks to be arranged in advance. It is not suitable for mobile application scenarios and greatly increases the hardware cost. difficulty and cost of use.

Technical solutions

The main purpose of the present invention is to overcome the above-mentioned defects in the prior art and propose a bow and arrow shooting simulation system and a bow and arrow shooting simulation method, which greatly enhance the real effect and provide a better experience.

The present invention adopts the following technical solutions:

A simulated shooting bow and arrow system, including a bow and arrow device and a simulation device. The bow and arrow device is provided with a bow handle, a bow string, an arrow shaft and a cylinder. Both ends of the bow string are fixedly connected to both ends of the bow handle, and the cylinder is fixed to the bow handle. The middle part and one end of it are closed, the arrow shaft is slidably installed in the barrel, and the end is provided with a through hole for the bow wire to pass through, and the arrow shaft is provided with a number of induction grooves; it is characterized in that: the bow and arrow device also includes There is a speed sensor, an aiming sensor, a main control module and a data transmission device. The speed sensor is installed on the cylinder to detect the induction groove information of the arrow shaft. The aiming sensor is installed on the cylinder to detect the arrow shaft in real time. Sensing data, the main control module is connected to the speed sensor, aiming sensor and data transmission device to calculate the off-string speed and Euler angle data when off-string based on the sensing slot information and sensing data and send it to the simulation device; the simulation The device obtains the elevation angle of the arrow shaft based on the Euler angle data, corrects the elevation angle based on the off-string speed and the set target distance, and then simulates the flight path of the arrow shaft based on the off-string speed and the corrected elevation angle and determines the target position.

Preferably, the speed sensor includes an infrared sensor. The arrow shaft is provided with several induction slots near the end. The infrared sensor is installed near the other end of the barrel to detect induction slot information. The main control module is connected to the infrared sensor. The sensors are connected to calculate the off-string speed based on the passage time and distance intervals of several induction slots; or, the speed sensor uses a Hall sensor, and the induction slot of the arrow shaft is equipped with a magnet, and the arrow is detected by the Hall sensor. Sensing slot information of the rod, the main control module is connected to the Hall sensor to calculate the string-off speed based on the passage time and distance interval of several sensing slots.

Preferably, the aiming sensor adopts a nine-axis sensor or a six-axis sensor, a three-axis geomagnetic sensor or a three-axis acceleration sensor, a three-axis gyroscope and a three-axis geomagnetic sensor. The Euler angle data includes a heading angle and a roll angle. and pitch angle.

Preferably, the data transmission device is a Bluetooth module or a WIFI module or a radio frequency module.

Preferably, the simulation device is a virtual reality device.

A simulation method for bow and arrow shooting, characterized in that, applied to the bow and arrow system for simulated shooting, it includes the following steps:

1) When shooting an arrow, the speed sensor detects the induction groove information of the arrow shaft, and the aiming sensor detects the sensing data of the arrow shaft. The main control module calculates the string-leaving speed based on the passage time and distance interval of several induction grooves. According to the sensing The Euler angle data when leaving the string is obtained from the data and sent to the simulation device;

2) The simulation device obtains the elevation angle of the arrow shaft based on the Euler angle data, and corrects the elevation angle based on the off-string speed and the set target distance;

3) The simulation device simulates the flight trajectory of the arrow shaft based on the off-string speed and the corrected elevation angle, and determines the target position based on the coordinates of the bullseye.

Preferably, in step 1), the aiming sensor adopts a nine-axis fusion algorithm, uses the angle value of the gyroscope for calculation when the aiming sensor moves quickly, and combines the parameters of the geomagnetometer and accelerometer for correction when the aiming sensor moves at low speed. , while using neighborhood filtering and Kalman filtering to improve the bumps and stuttering during angle correction, to obtain the sensing data.

Preferably, in step 2), the elevation angle is corrected based on the off-string speed and the set target distance, specifically calculating the angle correction value based on the off-string speed and the set target distance. angle2, and then compare the angle correction value angle2 with the elevation angle angle1 is superimposed to obtain the corrected elevation angle angle=angle1+angle2.

Preferably, set the starting coordinates of the arrow shaft (a1, a2), the bullseye coordinates (c1, c2), the off-string speed of the arrow shaft as V, and solve the angle correction value angle2 according to the following formula:

tan(angle2) = (-b ± (b^2 - 4*a*c)^0.5) / (2*a)

Where, a = 1/2 * g *Δz^2 / V^2, b = Δz, c = a –Δy, Δz is the difference between the starting coordinate and the bullseye coordinate on the Z axis and Δz = c1 - a1, Δy is the difference between the starting coordinate and the bullseye coordinate on the Y axis Value Δy = c2 - a2, g is the acceleration due to gravity.

Preferably, the flight trajectory of the arrow shaft is simulated according to the off-string speed and the corrected elevation angle as described in step 3), specifically: setting the starting coordinates (a1, a2) and target coordinates (b1, b2) of the arrow shaft ), the flight trajectory expression is as follows:

b1 = Vz * t + a1

b2 = Vy * t + 1/2 * g * t^2 + a2

Where, Vz is the component of the off-string velocity V on the z-axis and Vz = V * cos(angle), Vy is the component of the off-string velocity V on the y-axis and Vy = V * sin(angle), V is the off-string velocity of the arrow shaft, t is the flight time of the arrow shaft, angle is the corrected elevation angle, and g is the acceleration of gravity.

beneficial effects

From the above description of the present invention, it can be seen that compared with the prior art, the present invention has the following beneficial effects:

1. In the present invention, a speed sensor, an aiming sensor, a main control module and a data transmission device are provided on the bow and arrow device. The speed sensor detects the induction groove information of the arrow shaft, and the aiming sensor detects the sensing data of the arrow shaft in real time. The control module calculates the string-leaving speed and the Euler angle data when leaving the string based on the induction slot information and sensor data and sends it to the simulation device. The simulation device obtains the elevation angle of the arrow shaft based on the Euler angle data, and calculates the arrow shaft elevation angle based on the string-leaving speed and the set value. The elevation angle is corrected by fixing the target distance, and then the flight trajectory of the arrow shaft is simulated based on the off-string speed and the corrected elevation angle and the target position is determined, which greatly enhances the real effect and provides a better experience.

2. In the present invention, the speed sensor uses an infrared sensor. There are several induction slots near the end of the arrow shaft. The induction slot information is detected by the infrared sensor. The main control module calculates the distance from the string based on the passage time and distance interval of the several induction slots. Speed, the off-string speed calculated by this direct measurement is the true flight speed of the arrow shaft. The data is accurate and lays a good data foundation for the subsequent flight trajectory algorithm; when applied in the market, there is no need to add any traces on the bowstring or arrow shaft. Add other auxiliary sensor accessories to avoid user discomfort during operation and defects caused by collisions during arrow recovery. In addition, infrared sensors are cheap, low-cost, cost-effective, and have obvious economic effects.

3. In the present invention, the aiming sensor uses a nine-axis sensor to obtain the aiming angle data corresponding to the moment when the arrow shaft leaves the string, and uses a nine-axis fusion algorithm to calculate the angle value of the gyroscope when the aiming sensor moves quickly, and when the aiming sensor moves at a low speed, The parameters of the geomagnetometer and accelerometer are combined for correction, and neighborhood filtering and Kalman filtering are used to improve the bumpy and stuck sensor data during angle correction, reducing hardware costs and installation difficulty.

4. In real archery, the elevation angles of bows and arrows when shot are different at different arrow speeds and target distances. The user needs to adjust the sight to align with the bullseye. In order to simulate a real archery experience, the simulation device of the present invention can adjust the angle of the arrow according to the shape of the arrow shaft. The off-string speed and the set target distance automatically calculate the elevation correction value to correct the elevation angle, thereby simulating the true flight trajectory of the arrow shaft, which greatly enhances the real effect and can be used as a simulator for professional training.

Description of the drawings

Figure 1 is a structural diagram of the bow and arrow device of the present invention;

Figure 2 is a partial enlarged view of Figure 1;

Figure 3 is the system module diagram of the present invention

Figure 4 Flow chart of the method of the present invention;

Figure 5 is an exploded view of the actual flight angle of the arrow shaft of the present invention;

Figure 6 is a schematic diagram (10 meters) of the simulated flight trajectory of the simulation device of the present invention;

Figure 7 is a schematic diagram of the simulated flight trajectory (20 meters) of the simulation device of the present invention;

Figure 8 is a schematic diagram of the simulated flight trajectory of the simulation device of the present invention (30 meters);

in:

10. Bow handle, 20. Bow string, 30. Arrow shaft, 31. Sensing groove, 32. Through hole, 40. Cylinder, 50. Speed sensor, 60. Aiming sensor, 70. Main control module, 80. Data transmission device ,90. Simulation device.

The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

Embodiments of the invention

The present invention will be further described below through specific embodiments.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. The indicated orientation or positional relationship is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description. It does not indicate or imply that the device or element referred to must have a specific orientation or a specific orientation. construction and operation, and therefore should not be construed as limitations of the invention. Furthermore, the terms “first”, “second” and “third” are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that, unless otherwise clearly stated and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense. For example, it can be a fixed connection or a detachable connection. Connection, or integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediary; it can also be an internal connection between two components; it can be a wireless connection or a wired connection connect. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood on a case-by-case basis.

In the description of the present invention, it should be noted that the terms "upper", "lower", "one side", "other side", "one end", "other end", "side", "opposite", The orientations or positional relationships indicated by "four corners", "periphery", "mouth" structure, etc. are based on the orientations or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying. The structures referred to have a specific orientation, are constructed and operate in a specific orientation and are therefore not to be construed as limitations of the invention.

In addition, in the description of this application, "plurality" means two or more unless otherwise specified. "And/or" describes the association of associated objects, indicating that there can be three relationships. For example, A and/or B can mean: A exists alone, A and B exist simultaneously, and B exists alone. The character "/" generally indicates that the related objects are an "or" relationship.

Referring to Figures 1 to 3, a simulated shooting bow and arrow system includes a bow and arrow device and a simulation device 90. The bow and arrow device is provided with a bow handle 10, a bow string 20, an arrow shaft 30, a cylinder 40, a speed sensor 50, and an aiming sensor 60. , main control module 70 and data transmission device 80, etc. Both ends of the bow string 20 are fixedly connected to both ends of the bow handle 10 . The cylinder 40 is fixed at the middle part of the bow handle 10. It is a hollow structure with one end closed and an opening provided at the other end. The arrow shaft 30 is slidably installed in the barrel 40, and its end is located outside the barrel 40 and is provided with a through hole 32 for the bow wire to pass through. The arrow shaft 30 is provided with a plurality of induction grooves 31 near the end. The induction grooves 31 are arranged along the length direction of the arrow shaft 30 .

The speed sensor 50 is installed on the barrel 40 to detect the induction groove information of the arrow shaft 30 . Specifically, the speed sensor 50 includes an infrared sensor. The infrared sensor can be fixed on the cylinder 40 through the shell and is close to the other end of the cylinder 40. A corresponding hole is provided on the cylinder 40 to make way for the infrared sensor. The transmitting end and the receiving end are arranged toward the inside of the barrel 40. The transmitting end is used to emit infrared light to the arrow shaft 30 respectively, and the receiving end is used to receive the reflected signal. The emitted signal is the trigger level, which becomes a standard high and low level after being shaped by the comparison circuit. signal, the accuracy of the feedback time interval reaches 0.01ms. The outer periphery of the induction groove 31 on the arrow shaft 30 is coated with a color or substance that can absorb infrared light, such as black. That is, when the infrared light emitted by the infrared sensor hits the induction slot 31, it can be absorbed, and the receiving end cannot receive the reflected signal, thereby realizing the detection of the induction slot 31.

In the present invention, the number and distance of the induction slots 31 can be set as needed. For example, the number can be two, three or even more, preferably three. The infrared sensor can be used to detect the time point when each induction slot 31 passes, thereby obtaining the time period T of two adjacent induction slots 31, T=t1-t2, and the distance interval S of the adjacent induction slots 31 is known, Therefore, the off-string speed of the arrow shaft 30, that is, the true flight speed of the arrow shaft 30, can be calculated according to V=S/T. In practical applications, the speed sensor 50 can also use a Hall sensor, and a magnet can be provided in the induction groove 31 of the arrow shaft 30. The Hall sensor can detect the time point when each induction groove 31 of the arrow shaft 30 passes. The off-string velocity is calculated in the same way as for infrared sensors.

This invention uses an infrared sensor to detect speed, instead of performing indirect conversion based on the measured force, and does not need to use the mass of the arrow shaft to convert acceleration; it also avoids high-frequency sampling of acceleration and converts it into speed through time integration, using this direct measurement. The data obtained by this method are more accurate and cost-effective, laying a good data foundation for subsequent flight trajectory algorithms. At the same time, when used in the market, there is no need to add any auxiliary sensor accessories to the bow string or arrow shaft to avoid causing user errors during operation. Discomfort and defects caused by collision during flight recovery of the arrow shaft, and the infrared sensor is cheap, low-cost, and has obvious economic effects! The aiming sensor 60 is installed on the barrel 40 to detect the sensing data of the arrow shaft 30 in real time. Specifically, the aiming sensor 60 uses a nine-axis sensor to obtain X-Y-Z axis data, which may include three-axis acceleration, three-axis angular velocity, three-axis magnetic field data, etc., and obtains corresponding aiming angle data at the moment the arrow shaft 30 leaves the string, as Subsequent flight trajectory calculation provides real angle information. In practical applications, the aiming sensor can also use a six-axis sensor and a three-axis geomagnetic sensor, or a three-axis acceleration sensor, a three-axis gyroscope, and a three-axis geomagnetic sensor.

In the present invention, the deviation of the origin position of the magnetic induction sensor caused by the different geomagnetism of users around the world is taken into account (that is, the reset of the electronic compass to ensure that it can be recalibrated at different positions). When calculating the angular velocity of gravity, the velocity in the vertical direction can be decomposed through the angle of elevation. In this way, during the flight of the arrow, there will be a perfect parabolic flight trajectory, which more realistically reflects the effect of the arrow being shot out. Virtual reality (simulation) ) effect can be achieved.

The main control module 70 is connected to the speed sensor 50, the aiming sensor 60 and the data transmission device 80. It can calculate the string-leaving speed according to the time interval when the infrared sensor detects the adjacent sensing slots 31 and the distance interval between the adjacent sensing slots 31. And the Euler angle data is obtained after processing according to the sensing data detected by the aiming sensor 60 , and the off-string velocity and Euler angle data are sent to the simulation device 90 through the data transmission device 80 . In the present invention, the main control module 70 can use STM32, and the Euler angle data can include heading angle, roll angle, pitch angle, etc. The data transmission device 80 is a Bluetooth module, a WIFI module, a radio frequency module, etc., preferably a Bluetooth module (BK3431q).

The simulation device 90 obtains the elevation angle of the arrow shaft 30 based on the Euler angle data, corrects the elevation angle based on the off-string speed and the set target distance, and then simulates and determines the flight path of the arrow shaft 30 based on the off-string speed and the corrected elevation angle. Target location. The simulation device 90 of the present invention is a virtual reality device (VR), which can receive relevant data sent from the data transmission device 80 and use Unity3d to simulate the flight trajectory of the arrow shaft 30 through the off-string speed and the corrected elevation angle.

Based on this, the present invention also proposes a bow and arrow shooting simulation method, which is applied to the above-mentioned bow and arrow simulation shooting system. See Figure 4, which includes the following steps:

1) When shooting an arrow, the speed sensor 50 is used to detect the induction groove 31 of the arrow shaft 30, and the aiming sensor 60 is used to detect the sensing data of the arrow shaft 30 in real time. The main control module 70 calculates it based on the passage time and distance interval of several induction grooves 31. As for the velocity of leaving the string, the Euler angle data when leaving the string is obtained according to the sensing data and sent to the simulation device 90;

In this step, the infrared sensor can be used to detect the time point when each induction slot 31 passes, thereby obtaining the time length T of two adjacent induction slots 31, T=t1-t2, and the distance between the adjacent induction slots 31 is S is known, therefore, the main control module 70 can calculate the off-string speed, that is, the true flight speed of the arrow, based on V=S/T.

The aiming sensor 60 adopts a nine-axis fusion algorithm. When the aiming sensor 60 moves quickly, it uses the angle value of the gyroscope for calculation, and when the aiming sensor 60 moves at a low speed, it combines the parameters of the geomagnetometer and accelerometer for correction. It also uses neighborhood filtering and Kalman filtering is used to improve the bumps and stucks during angle correction to obtain sensing data. The main control module 70 processes the sensing data to obtain Euler angle data, including heading angle, roll angle, pitch angle, etc.

Among them, Kalman filtering is an algorithm that allows the obtained data to continuously approach the actual data. It mainly fuses the state variables with the observed variables to obtain data close to the real data, and then uses it as the state variable of the next process, and then combines it with the state variable of the next process. The observed variables are fused, and so on, the final data will be very close to the real data.

Neighborhood filtering: Smoothing filtering in the spatial domain is generally performed using the simple averaging method, which is to find the average brightness value of adjacent pixel points. The size of the neighborhood is directly related to the smoothing effect. The larger the neighborhood, the better the smoothing effect. However, if the neighborhood is too large, the smoothing will cause greater loss of edge information, thus making the output image blurred, so it needs to be selected appropriately. The size of the neighborhood.

The present invention uses a nine-axis sensor to measure and calculate the flight angle of the arrow shaft, and uses an accelerometer to detect the direction of gravity; and then uses an accelerometer and a gyroscope to obtain a more accurate inclination of the equipment and the ground plane, where acceleration has a significant impact on general vibration and Mechanical noise is very sensitive, and a gyroscope is used to smooth the output of the accelerometer; however, the gyroscope accumulates errors, and a magnetometer is used to correct the problem that the axial data perpendicular to the ground always drifts.

2) The simulation device 90 obtains the elevation angle of the arrow shaft 30 based on the Euler angle data, and corrects the elevation angle based on the off-string speed and the set target distance.

Referring to Figure 5, assume that vector R is the true flight angle of arrow shaft 30 as detected by aiming sensor 60. The X-axis is the horizontal direction, the Y-axis is the direction perpendicular to the horizontal direction, and the Z-axis is the axial direction. X, Y, and Z are the angles between the vector R and the X, Y, and Z axes respectively; Rx, Ry, and Rz are the projections of the vector R on the X, Y, and Z axes, respectively. then there is

cosX = cos(Axr) =Rx/R

cosY = cos(Ayr) =Ry/R

cosZ = cos(Azr) =Rz/R

The above three formulas are often called directional cosines and reflect that the unit vector r (a vector of length 1) and the R vector have the same direction. And there is also the following relationship:

cos²X+cos²Y+cos²Z=1

Further, Rxz is the projection of the vector R on the XZ plane, Ryz is the upper projection of the vector R on the YZ plane, and Rxy is the upper projection of the inertial force vector R on the XY plane. Ayz is the angle between the projection Ryz of the vector R on the YZ plane and the Z axis, and Axz is the angle between the projection Rxz of the vector R on the XZ plane and the Z axis. In the present invention, the obtained angle is the angle between the projection of the vector R on the YZ axis, which is the elevation angle angle1=Ayz. Among them, the Y-axis is the direction perpendicular to the horizontal direction, which is the horizontal flight direction of the arrow, and the Z-axis is the axial direction, which is the vertical flight direction of the arrow.

In real archery, the elevation angle of the arrow shaft 30 when shooting is different at different arrow speeds and different target distances. The user needs to adjust the sight to align with the target. In the present invention, in order to simulate a real archery experience, the simulation device 90 can automatically calculate the elevation correction value according to the off-string speed of the arrow shaft 30 and the set target distance to correct the elevation angle.

In the present invention, the angle correction value angle2 is calculated based on the off-string velocity and the set target distance, and then the angle correction value is The angle2 and the elevation angle angle1 are superimposed to obtain the corrected elevation angle. angle=angle1+angle2.

Set the starting coordinates of the arrow shaft 30 (a1, a2), the bullseye coordinates (c1, c2), and the off-string speed of the arrow shaft 30 as V, then there is the following relationship:

Δz = c1 - a1;

Δy = c2 - a2;

Vz = V* cos(angle2);

Vy = V* sin(angle2);

Vy * t + 1/2 * g *t^2 = Δy;

Vz * t = Δz;

t = Δz / Vz;

Among them, Δz is the coordinate difference between the starting coordinate and the target coordinate on the z-axis; Δy is the coordinate difference between the starting coordinate and the target coordinate on the Y-axis; Vz is the velocity component of V in the Z-axis direction; Vy is V is the velocity component in the Y-axis direction; g is the acceleration due to gravity.

Satisfy the following relationship:

(V* sin(angle2)) * Δx / (V * cos(angle2)) + 1/2 * g * Δz^2 / (V^2*cos(angle2)^2) = Δy

tan(angle2) * Δz + 1/2 * g * Δz^2 / (V^2*cos(angle2)^2) = Δy

Further get:

tan(angle2) * Δz + 1/2 * g * (Δz^2 / V^2) * (1 + tan(angle2)^2) = Δy.

Let a = 1/2 * g *Δz^2 / V^2, b = Δz, c = a –Δy, then there is:

tan(angle2) = (-b ± (b^2 - 4*a*c)^0.5) / (2*a)

Let d = tan(angle2) , then angle2 = arctan(d).

3) The simulation device 90 simulates the flight trajectory of the arrow shaft 30 based on the off-string speed and the corrected elevation angle and determines the target position in combination with the coordinates of the bullseye.

The flight trajectory of the arrow shaft 30 is simulated based on the off-string speed and the corrected elevation angle, specifically: setting the starting coordinates (a1, a2) and the target coordinates (b1, b2) of the arrow shaft 30, there is the following relationship:

Vz = V* cos(angle)

Vy = V* sin(angle)

Vy * t + 1/2 * g * t^2 = Δy

Vz * t = Δz

Then the flight trajectory expression is as follows:

b1 = Vz * t + a1

b2 = Vy * t + 1/2 * g * t^2 + a2

Among them, V is the off-string speed of the arrow shaft 30, Vz is the component of the off-string speed V on the z-axis, Vy is the component of the off-string speed V on the y-axis, t is the flight time of the arrow shaft 30, and angle is the corrected elevation angle. , g is the acceleration due to gravity.

In this step, the simulation device 90 simulates the flight trajectory of the arrow shaft 30, and then associates it with the target coordinates (such as a target, etc.) in the space scene to obtain the target position and create the effect of the arrow shaft 30 flying and hitting the target. , see Figure 6-Figure 8. The simulation device of the present invention is also equipped with a network interaction function, so that the user can have an archery competition with friends across space at any place.

The above are only specific embodiments of the present invention, but the design concept of the present invention is not limited thereto. Any non-substantive changes to the present invention using this concept shall constitute an infringement of the protection scope of the present invention.

Claims

A simulated shooting bow and arrow system, including a bow and arrow device and a simulation device. The bow and arrow device is provided with a bow handle, a bow string, an arrow shaft and a cylinder. Both ends of the bow string are fixedly connected to both ends of the bow handle, and the cylinder is fixed to the bow handle. The middle part and one end of it are closed, the arrow shaft is slidably installed in the barrel, and the end is provided with a through hole for the bow wire to pass through, and the arrow shaft is provided with a number of induction grooves; it is characterized in that: the bow and arrow device also includes There is a speed sensor, an aiming sensor, a main control module and a data transmission device. The speed sensor is installed on the cylinder to detect the induction groove information of the arrow shaft. The aiming sensor is installed on the cylinder to detect the arrow shaft in real time. Sensing data, the main control module is connected to the speed sensor, aiming sensor and data transmission device to calculate the off-string speed and Euler angle data when off-string based on the sensing slot information and sensing data and send it to the simulation device; the simulation The device obtains the elevation angle of the arrow shaft based on the Euler angle data, corrects the elevation angle based on the off-string speed and the set target distance, and then simulates the flight path of the arrow shaft based on the off-string speed and the corrected elevation angle and determines the target position.
A simulated shooting bow and arrow system as claimed in claim 1, characterized in that: the speed sensor includes an infrared sensor, and the infrared sensor is installed near the other end of the cylinder to detect induction slot information, and the main control The module is connected to an infrared sensor to calculate the off-string speed based on the passage time and distance intervals of several induction slots; or, the speed sensor uses a Hall sensor, and the induction slot of the arrow shaft is equipped with a magnet, and the speed is measured through the Hall sensor. The sensor detects the induction slot information of the arrow shaft, and the main control module is connected to the Hall sensor to calculate the string-leaving speed based on the passage time and distance interval of several induction slots.
A bow and arrow system for simulated shooting according to claim 1, characterized in that: the aiming sensor adopts a nine-axis sensor, and the Euler angle data includes a heading angle, a roll angle and a pitch angle.
A simulated shooting bow and arrow system according to claim 1, characterized in that the data transmission device is a Bluetooth module, a WIFI module or a radio frequency module.
A bow and arrow system for simulated shooting according to claim 1, characterized in that: the simulation device is a virtual reality device.
A method for simulating bow and arrow shooting, characterized in that it is applied to a simulated shooting bow and arrow system according to any one of claims 1-5, and includes the following steps:

1) When shooting an arrow, the speed sensor detects the induction groove information of the arrow shaft, and the aiming sensor detects the sensing data of the arrow shaft in real time. The main control module calculates the string-leaving speed based on the passage time and distance interval of several induction grooves. The Euler angle data when leaving the string is obtained from the sensed data and sent to the simulation device;

2) The simulation device obtains the elevation angle of the arrow shaft based on the Euler angle data, and corrects the elevation angle based on the off-string speed and the set target distance;

3) The simulation device simulates the flight trajectory of the arrow shaft based on the off-string speed and the corrected elevation angle, and determines the target position based on the coordinates of the bullseye.
A simulation method for bow and arrow shooting according to claim 6, characterized in that in step 1), the aiming sensor adopts a nine-axis fusion algorithm, and when the aiming sensor moves quickly, the angle value of the gyroscope is used for calculation, and The sensing data is obtained by combining the parameters of the geomagnetometer and accelerometer during the low-speed movement of the aiming sensor, and using neighborhood filtering and Kalman filtering to improve the bumps and freezes during angle correction.
A simulation method for bow and arrow shooting according to claim 6, characterized in that in step 2), the elevation angle is corrected according to the string departure speed and the set target distance, specifically according to the string departure speed and the set target distance. Calculate the angle correction value angle2 for the target distance, and then adjust the angle correction value The superposition of angle2 and elevation angle1 yields the corrected elevation angle angle=angle1+angle2.
A simulation method for bow and arrow shooting as claimed in claim 8, characterized in that the starting coordinates of the arrow shaft (a1, a2), the bullseye coordinates (c1, c2) are set, and the off-string speed of the arrow shaft is V, Solve the angle correction value angle2 according to the following formula:

tan(angle2) = (-b ± (b^2 - 4*a*c)^0.5) / (2*a)

where, a = 1/2 * g *Δz^2 / V^2, b = Δz, c = a –Δy, Δz is the difference between the starting coordinate and the bullseye coordinate on the Z axis and Δz = c1 - a1, Δy is the starting coordinate and the bullseye coordinate Difference on Y axis Δy = c2 - a2, g are the acceleration due to gravity.
A simulation method for bow and arrow shooting according to claim 6, characterized in that: in step 3), the flight trajectory of the arrow shaft is simulated according to the off-string speed and the corrected elevation angle, specifically: setting the arrow shaft The starting coordinates (a1, a2), target coordinates (b1, b2), and the flight trajectory expression are as follows:

b1 = Vz * t + a1

b2 = Vy * t + 1/2 * g * t^2 + a2

Among them, Vz is the component of the off-string velocity V on the z-axis and Vz = V * cos(angle), Vy is the off-string velocity V has a component on the y-axis and Vy = V * sin(angle), V is the off-string velocity of the arrow shaft, t is the flight time of the arrow shaft, angle is the corrected elevation angle, and g is the acceleration due to gravity.